Intensity-modulated Parametric Mapping for Simultaneous Display of Rapid Dynamic and High-Spatial-Resolution Breast MR Imaging Data

Abstract

Contrast material-enhanced magnetic resonance (MR) imaging of the breast has variable specificity for differentiation of breast cancer from other enhancing conditions. Two principal strategies to improve its specificity are rapid dynamic MR imaging and high-spatial-resolution MR imaging. A method was developed of combining contemporaneously acquired dynamic and high-spatial-resolution MR imaging data into a single integrated display. Whole-breast rapid dynamic data were condensed into a color map by using pharmacokinetic analysis. The pharmacokinetic results were combined with the high-spatial-resolution images with a new technique that preserves underlying morphologic details. This new method was evaluated by five radiologists for eight breast lesions, and the results were compared with those of the standard method of overlaying parametric map data. The radiologists' ratings showed a statistically significant preference for the intensity-modulated parametric map display method over the overlaid parametric display method for 10 of the 12 evaluation criteria. The new method enabled simultaneous visualization of pharmacokinetic and morphologic information, facilitated assessment of lesion extent, and improved the suppression of noise in the pharmacokinetic data. The ability to simultaneously assess both dynamic and high-spatial-resolution features may ultimately improve the specificity of breast MR imaging.

Breast magnetic resonance image screening and ductal lavage in women at high genetic risk for breast carcinoma

“…Contrast-enhanced images were obtained using an interleaved rapid dynamic and highspatial-resolution protocol designed to capture the rate of enhancement as well as the morphologic features of any enhancing lesion during and after a single-bolus, antecubital, intravenous injection of 0.1 mmol/kg gadolinium contrast agent. 32 Initial dynamic imaging consisted of whole-breast, 3-dimensional spiral images 33 34 (TR, 33; TE, 9 msec; flip angle, 50 degrees; FOV, 20 cm; matrix, 512 ϫ 192 pixels; number of slices, 63; slice thickness, 1.5-2.0 mm; with water-selective, spectral-spatial excitation on resonance 1-2-1 MT suppression pulse). An additional 260 seconds of dynamic imaging were performed immediately after the high-resolution scan to capture the rate of wash-out of contrast from the breast.…”

Evaluation of quantitative parametric analysis for characterization of breast lesions in contrast-enhanced MR mammography

“…During the last few years, a wide range of image acquisition protocols and image interpretation systems has been developed for evaluating breast magnetic resonance (MR) imaging studies with the attempt to increase specificity and standardization of MR mammography [1][2][3][4][5][6][7][8][9]. Two basic approaches of image interpretations have been used for differentiating malignant from benign lesions: contrast-enhancement kinetics (requiring good temporal resolution) and morphological analysis of lesions (requiring good spatial resolution) [10,11].…”

Combination of low and high resolution sequences in two orientations for dynamic contrast-enhanced MRI of the breast: more than a compromise

“…The initial phase of CM uptake, maximum relative enhancement and washout in the late post-contrast phase turned out to be the most valuable criteria to assess the likelihood of malignancy of a lesion among other parameters. This enabled the description of different dynamic curve types [11] and the improvement of visualization by parametric imaging [16,17]. Signal-time curves get more precise using many sequences with short acquisition times [18].…”